Cloth-cutting machine knife sharpener



July 8, 1947.

CLOTH-CUTTING MACHINE KNIFE SHARPENER 2 Sheets-Sheet 1 Filed Feb. 19, 1946 M. STEINER 2,423,570

lll l ll //V [/5 N TOR. M05 57E/A/ER July 8, 1947. M. S TEINER CLOTH-CUTTING MACHINE KNIFE SHARPENER Filed.Feb. 19, 1946 I 2 Sheets-Sheet 2 fE/NER Moe 5 arrow/57 Patented July 8, 1947 CLOTH-CUTTING MACHINE KNIFE SHARPENER Moe Steiner, Brooklyn, N. Y.

Application February 19, 1946, Serial No. 648,743

7 Claims.

This invention relates to new and useful improvements in cloth-cutting machines.

The invention more specifically relates to a cloth-cutting machine of the reciprocating knife type in which the knife is mounted on a crosshead which is reciprocated by a pitman connected with a crank on a flywheel driven by the motor of the machine. It is customary to have a hollow cover engaged over the crosshead, the pitman and the flywheel. An important object of this invention resides in providing the hollow cover with recessed bottom side portions for receiving grindstones for sharpening the knife. It is proposed to mount the knife forwards of the crosshead on a lug projecting from the crosshead so that the cover may berecessed as stated. With this construction it is possible to locate the grindstones directly above the knife, when they are not in use, and it is possible to provide a simple cam means which will move the grindstones towards and against the knife when they are lowered a sufiicient distance so as to clear the bottom of the hollow cover.

Another important object of this invention resides in the construction of the cam means for controlling the inward and outward movements of the grindstones. It is also proposed that the cloth-cutting machine be provided with a vertical slide for moving the grindstones up and down along the knife for sharpening purposes. Another object of the invention resides in the pro- Vision of a vertical cylindrical member rotatively mounted on a support which is provided with guideways for said slide. It is proposed that the vertical cylindrical member be provided with an endless peripheral thread with a section thereof extending down and continuin into a section extendin up and connecting with the top of said downwardly extending section. Means is provided for rotating said cylindrical member. t is proposed to mount a follower on the slide engaging said endless peripheral thread for reciprocating the slide.

Another object of this invention is to provide a main drive shaft for the grindstones arranged through a hollow coaxially in the cylindrical member referred to above. A thrust bearing is provided for said main drive shaft mounted on said slide so that the drive shaft will be extended downwards from and then be moved upwards back into the cylindrical member during the reciprocation of said slide. A drive is provided for driving said main drive shaft in all of its positions.

pivotally mounted on the main drive shaft referred to above and supporting said grindstones in positions in which they are normally disposed in the recessed bottom side portions of the hollow cover previously mentioned. Drive transmissions connect the main drive shaft with the grindstones for drivin them.

Another object of this invention resides in the construction of a particularly simple and effi' cient mechanism for operating the slide for moving the grindstones along the knife for sharpening purposes. It is proposed to characterize this mechanism by a friction drive wheel adapted to normally engage the flywheel of the clothcutting machine and connected for controlling the operation of the slide. It is proposed that the friction wheel be manually controlled for engaging the flywheel and that it be automatically disconnected from the flywheel after the slide performs one complete cycle of its operation.

Another object of the invention is the construction of a device as described, which is simple and durable and which may be manufactured and sold at a reasonable cost.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

Fig. 1 is a side elevational view of a cloth-cutting machine constructed in accordance with this invention.

Fig. 2 is a front view of Fig. 1.

Fig. 3 is a fragmentary enlarged vertical sectional view taken on the line 3-3 of Fig. 2.

Fig. 4 is a horizontal sectional View taken on the line 4-4 of Fig. 3.

Fig. 5 is a horizontal sectional view taken on the line 5-5 of Fig. 3.

Fig. 6 is a fragmentary vertical sectional view taken on the line 6-6 of Fig. 3.

Fig. 7 is a fragmentary sectional view taken on the line ll of Fig. 2. I

The new and improved cloth-cutting machine, in accordance with this invention, includes the usual housing If] having a base II and a standard I2. The standard [2 is formed with a vertical slot M in which the reciprocating knife I5 is mounted. The housing [0 is provided With a handle it by which it may be conveniently guided. An electric motor I! is mounted on the top por- The invention also proposes horizontal arms t n 0f the housing I9 and is Controlled With t usual switch I8. The electric motor I! is connected to drive a flywheel which is provided with a crank pin 2| connected with a pitman 22, in turn connected with a crosshead 23 which is vertically slidably engaged in guideways 24 mounted within the housing Ill. The housing ID has a small top handle 25 by which the clothcutting machine may be easily carried.

Up to thispoint the cloth-cutting: machine is of standard; construction. It now difiers in. the fact that the crosshead 23 is provided with a front lug 21 for supporting the knife l5. upper end of the knife l5 engages the lug 21 and is releasably held by a fastening screw' 28; hollow cover 30 is mounted upon the front of the housing In and encloses the flywheel 25-; the pitman 22, and the crosshead 23. Prior cloth-cutting machines are provided with hollow covers similar to the cover 30. cover 30 distinguishes from the prior constructions in the fact that it is provided with. recessed bottom side portions. 5!" adapted to form nooks into which the grindstones 32' engage in their inoperative positions. In prior constructions, the knife 15 is attached to the bottom of the crosshead-23". The purpose of mounting it tothe front of the crosshead 23 is to place the edge of. the knife l5 directly behind the recessed bottom side portions 3'! so that the grihdstones 3.2 are substantially. inposition for. engaging the edge of the knife l5when moved but slight d'istancestowards. each other. Furthermore, because the grind'stones 32 are normally housed in the recessed bottom side portions 3| they donot pr.o .iect very far from thesides of the housing. iii.

A guard bar 36 ispositioned aslight distance to the front of the knife I5. This guard. bar

is slidably mounted in spaced bearings 31 and 38.mountedon-.the front of the cover 30. Ahandle 39 is mounted. on the top of'the guard. bar 36 by which. it may be easily raised. A presser foot40ii's mounted on. the bottom. of the guardbar 35; The guard bar 35. is. associated. with means by which it may be, latched in various elevated. positions. This. means includes a. rod 42? turnably. mounted in. a bearing '43 which is on the. front, of. the. cover. 3131 upon. the rod142 and. is engageable against the back of'the. guard bar 35ffor forcing it forwards so as to frictionally. bind it in the bearings 31 and38. The outer end. of the-rod 42 is provided with a handle by which the. cam 44 may be disengaged from the guard bar 36: to free it. A spring. 41 is connected with the handle 45 and- With the cover 30 and acts tonormally urge the cam 44 against the guardbar 36. for latching it in fixed positions. 1

A support 59. is fixedly. mounted a short distance to the front of thecover 3 0- by abottom bracket 5|. A pair of top brackets-53 are mounted between. the support. and the cover 30 and serve to assist in firmly holding. the support 5.5 The support. 50 is. provided with vertical guideways 54. A vertical slide 5.5.slidably engagesthe' guideways 54. This slide 55 is hollow and of semi-circular form and acts to house certain mechanism. for vertically reciprocating the slide 55... Thismechanism includes a vertical cylindrical. member 56 which is rotatively supported atthetop. upona bracket 57 and at thebottom upon. abracket 58. These brackets 51 and 53 are mountedupon thesupport 50.

'Ilhe. vertical. member 56 isprovided with an endless. peripheral thread 59 havinga; section. extending down. and. continuing intoa section:

The:

A- cam 44 isv mounted- However; this meshes with said gear 82.

extending up and connecting with the top of the downwardly extending section. A follower 59 is mounted on the slide 55 and engages the endless peripheral thread 59 for reciprocating the slide 55 when the vertical cylindrical mem ber 56 is rotated. This follower 69 is in the nature of a fork El engaging the thread 59 and turnably supported by a shank portion 62 which engages: into. a hollow casing t3 which in turn is mounted upon the slide 55. A. spring 54 is housed in the casing 53 and resiliently urges the fork 61 into engagement with the thread 59. The ends of the fork'tl are suitably beveled or pointed sot as: to permit the follower 68 to negotiate all the turns necessary to maintain contact with the thread 59 while the cylindrical member 55 is rotated. The shank portion 62 projects from the slide 55 and has an external knob 65 by which the: shank portion 62 may be pulled outwards to disengage the fork 6| from the thread 59 to free the slide 55 which may then be removed from the guideways 54.

A worm wheel 65 is mounted uponthe bottom end of the. cylindricalmember 56 and is engaged by a worm pinion. 5'! on a shaft $3.8 rotatively mounted between the bracket 58 and the support 59. A main drive shaft 7.!) for the grindstones 32 extends coaxially through the cylindrical member 56 which is hollow for this purpose. The drive. shaft 1!! is non-circular in transverse cross section, preferably square, and engages a complementary non-circular opening in a bushing ll rotatively mounted at the bottom of the cylindrical member 56. The bushing H is provided -with a worm wheel 12 which is engaged by a worm pinion 13 on a shaft 14 rotatively mounted upon the bracket 58 and the support 58. Spur gears and T6. are mounted on the shafts (i is fixedly mounted on the bushing 94 and extends radially along the other side of the gear 19'. A gear 82 is mounted between the arms Bland 8i and meshes with said gear 19'. The arm 8! has a bearing bushing 84 through which a shaft 83 extends. A gear 82 is mounted on shaft 83 and The shaft 83 has a bearing in arm 8 l. The shaft 81% isprovided with a friction drive wheel 88 which is adapted to engage the flywheel 29. between the arm 8! and the support 53 and normally urges the arm 8! downwards so as to frictionally engage the friction wheel 86 against-the flywheel 2.5. A casing 8'! is mounted over the.

friction wheel 86. A brake spring 88 is mounted Within. the casing Bl a. slight distance above the frictionwheel 86 so-that when thefriction drive wheel 86 is lifted to disengage from theflywhecl 211i itwill engage the brake 88 and be instantly stopped.

The arms. 8i and 8! have upwardly projecting This train of gears 75' A spring 8? is connected.

and the head 93 for normally urging the stem portion 92 forwards. An element 95 projects from the slide 55 and is adapted to engage beneath the head 93 of the depressible member 9| when the slide 55 reaches its top position for lifting the arms BI and BI so as to disengage the friction drive wheel 85 from the flywheel 20. A rod 95 is turnably mounted in bearings 91 mounted on the support 59. A radial arm 98 is mounted on the rod 95 and has a substantially vertical slot 98' into Which'a pin 99 mounted on the stem portion 92 engages. An arm I50 is mounted on the rod 95 directly in front of the guard rod 36. The rod 93 is provided with a handle Illl by which it may be turned. When the guard rod 35 is in a raised position the handle Gel cannot be moved to cause the arm 93 to move the stem portion 92 rearwards because the arm |09 strikes the guard rod 35. When the guard rod 35 is in its bottom position the handle may be moved to turn the rod 95 so that the arm 98 moves the stem portion 92 rearwards for moving the depressible member 9| rearwarcls and off the element 95. It should be noted that when the guard rod 35 is in a raised position it prevents the grindstones 32 sharpening the knife I 5.

The grindstones 32 are rotatively supported on horizontal arms I05, I05, l0? and M9. The front ends of these arms pivotally engage upon the bottom portion Ill of the drive shaft 10, this bottom portion being circular sothat said arms are free to pivot. The circular portion E9 of the main drive shaft l0 engages through a thrust bearing H9 which is mounted on the slide 55. The horizontal arms I and I96 are superimposed in respect to each other and support one of the grindstones 32, while the arms I91 and I08 are superimposed with respect to each other and support the other grindstone 32. A spring H2 is connected between the arms H35 and i0! for urging them towards each other. A spring M3 is connected between the arms I93 and IE3 for urging them together.

The horizontal arms H35 and 101 are provided with upwardly extending fingers H4 which are provided with rollers H5 at their top ends. These rollers |I5 engage the sides of a cam H5 mounted on the front of the hollow cover 39. The cam H9 has straight sides except at the bottom where it is formed into a pointed portion H1. The springs H2 and H3 maintain the rollers 5 against the sides of the cam I I 6. However, when the slide 55 moves downwards, and when the grindstones 32 are beneath the bottom of the hollow casing 30, then the rollers ||5 reach the pointed portion ii! of the cam H5 and following the pointed portion IlI allows the springs H2 and H3 to move the grindstones 32 towards each other and against the knife 55.

A spur gear I is mounted upon the bottom portion I0 of the shaft l0 and meshes with a gear I2! mounted upon the arm I01 which in turn meshes with a gear I22 connected with one of the grindstones 32'. The gear I20 also meshes with a gear I23 which meshes with a gear I24. These latter two gears I23 and I24 are mounted on the horizontal arm I05. The gear I24 meshes with a gear I25 mounted upon the other grindstone 32. The grindstones 32 are helical and the threads of the heliXes are so arranged that when the grindstones 32 are together in sharpening position engaging the knife I5, the threads mesh with each other. Because of the helical form of the grindstones 32, the grinding operation will be continuous.

The operation of the device is as follows: Normally, the grindstones 32' are in raised positions housed within the recessed bottom side portions 3| of the hollow cover 30. The depressible member 9| is held in a slightly raised position by the element 95. The friction wheel 86 is not con tacting the flywheel 20. Now the electric motor I! operates the crank pin 2| on the flywheel 20, and through the pitman 22, and the crosshead 23, reciprocates the knife I5. The cutting machine is used in this condition. When it is desired to sharpen the knife I 5 the operator merely pivots the rod 96 by moving the handle IOI. However, this cannot be done unless the presser foot 59 is in its extreme bottom position. It is necessary to move the presser foot handle 45 to cause the cam 44 to release the guard bar 36. Then the guard bar 39 drops to its bottom position and the presser foot 40 is now at its bottom position.

When the handle |0I is moved the arm 98 is pivoted and because of the pin 99 on the stem portion 92 engaging the slot 98', the depressible member 9| is moved to a position in back of the element 95. The spring 81 now pivots the arms 8| and 8| downwards and engages the friction wheel 86 against the flywheel 20.

Rotations from the flywheel 29 will be transmitted by th friction whee1 86 to the gear 82, the gear 82", the drive gear 79', the train of gears I9,

o the gear l8, and the gears 15 and I6 to drive the shafts 68 and 14. The shaft 68 indirectly drive the cylindrical member 55. The shaft 14 indirectly drives the main drive shaft I0.

Rotations of the cylindrical member 56 causes the follower 90 to move the slide 55 downwards and then upwards back to its initial position. This represents one cycle of operation of the slide 55. During this cycle, while the slide 55 is moving downwards, the rollers I I5 travel along the sides of the cam I I5 until the grindstones 32 reach positions beneaththe hollow cover 30. Now the springs H2 and H3 pivot the arms I05, I06, I01 and I09 and cause the grindstones 32 to move towards each other and engage the knife I5. The slide 55 continues downwards and during this period the knife I5 will be sharpened because the grindstones 32 are being driven. Rotations from the shaft ill will indirectly drive the grindstones 32 in opposite directions because of the gear I20 and the trains of gears meshing with this gear.

When the slide 55 reaches its bottommost position it starts moving upwards. The grinding operation continues until the rollers I I5 engage the point II! of the cam IIB. This separates the grindstones 32. When the slide 55 reaches its uppermost position the grindstones 32 will again be housed in the bottom recessed portions 3|. The element will come up and strike the bottom of the depressible member 9| lifting the arms 8| and 32 and causing the friction wheel 86 to disconnect from the flywheel 29. This automatically disconnects the sharpening means.

While I have illustrated and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the precise construction herein. disclosed and the right is reserved to all changes andmodifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. In a cloth-cutting machine of the reciprocating knife type having a cross-head for the knife vertically slidably mounted in a housing, a narrow lug. for. supporting said knifeprojecting forwardscentrally from said cross head, a hollow cover mounted on said housing and over said cross-head and having'recessed bottom side portions for receiving grindstones for sharpening saidknife, said recessed bottom side portions being positionedto the sides of said lug, a support mounted on the front of said hollow cover, a vertical: slide slidably mounted on said support, horizontal arms pivotali'y mounted on said slide, grindstones mounted on said arms and normally disposed recessed bottom side portions, cam means iz'lciuding a cam mounted on the front of said cover for moving said arms towards each other when said slide moves down a sufiicient distance for said grindstones to clear the bottom of said hollow cover for engaging said grindstones against said knife.

2, In a clotf-cutting machine of the reciproeating knife type having a cross-head for the knife vertically slidably mounted in a housing, a narrow for supporting said knife projecting forwardly centrally from said cross head, a hollow cover mounted on said housing and over said cross-head and having recessed bottom side portions for receiving grindstones for sharpening said knife, said recessed bottom side portions being positioned to the sides of said lug, a support mounted on the front of said hollow cover, a vertical slide slidably mounted on said support, horizontal arms pivotally mounted on said slide, grindstones mounted on said arms and normally disposed in said recessed bottom side portions, and cam means including a cam mounted on the front of said cover and having straight sides and a pointed bottom portion for moving said arms towards each other when said slide moves down a sufficient distance for said grindstones to clear the bottom of said hollow cover for engaging said grindstones against said knife.

3. In a cloth-cutting machine of the reciprocating knife type having a cross-head for the knife vertically slidably mounted in a housing, a narrow lug for supporting said knife projecting forwards centrally from said cross head, a hollow cover mounted on said housing and over said cross-head and having recessed bottom side portions for receiving grindstones for sharpening said knife, said recessed bottom side portions bepositionedto the sides of said lug, a support mounted on the front of said hollow cover, a vertical slide slidably mounted on said support, horizontal arms pivotally mounted on said slide, grindstones mounted on said arms and normally disposed in said recessed bottom side portions, and cam means including a cam mounted on the front of said cover and having straight sides and a pointed bottom portion for moving said arms towards each other when said slide moves down a sufficient distance for said grindstones to clear the bottom of said hollow cover for engaging said grindstones against said knife, said cam means also including upwardly projecting fingers on said horizontal arms for following said cam.

i. In a cloth-cutting machine of the reciprocating knife type having a cross-head for the knife vertically slidably mounted in a housing, a narrow lug for supporting said knife projecting forwards centrally from said cross head, a hollow cover mounted on said housing and over said cross-head and having recessed bottom side portions for receiving grindstones for sharpening said knife, said recessed bottom side portions being positioned to the sides of said lug, a support mounted on the front of said hollow cover, a ver- 8 ticalslideslidably mounted'on said support, horizontal arms pivotally mounted on said slide, grindstones mounted on said arms and normally disposed in said recessed bottom side portions, and cam means including a cam mounted on the front of said cover and having straight sides and a pointed bottom portion for moving said arms towards each other when said slide moves down a sumcient distance for said grindstones to clear the bottom of said hollow cover for engaging said grindstones against said knife, said cam means also including upwardly projecting fingers on said horizontal arms, and rollers on said fingers engaging the sides of said cam.

5'. In a cloth-cutting machine of the reciprocating knife type having a vertical slide for moving grindstones along the knife for sharpening purposes, a support having guideways for said slide, a vertical cylindrical member rotatively mounted on said support and having an endless peripheral thread with a section extending down and continuing into a section extending up and connecting with the top of said downwardly extending section, means for rotating said cylindrical member, a follower mounted on said slide and engaging said endless peripheral thread for reciprocating said vertical slide, a main drive.

shaft for said grindstones extending coaxially through a hollow in said cylindrical member, a thrust bearing for said drive shaft mounted on said slide, and drive means for said main drive shaft, including a rotatively mounted drive bushmg having an opening complementary to the shape of said main drive shaft through which said main drive shaft passes for non-rotative and slidable connection with the bushing, a Worm wheel mounted on said drive bushing, and a worm pinion engaging said worm wheel.

6. In a cloth-cutting machine of the reciprocating knife type having a vertical slide for moving grindstones along the knife for sharpening purposes, a support having guideways for said slide, a vertical cylindrical member rotatively mounted on said support and having an endless peripheral thread with a section extending down and continuing into a section extending up and connecting with the top of said downwardly extending section, means for rotating said cylindrical member, a follower mounted on said slide and engaging said endless peripheral thread for reciprocating said vertical slide, a main drive shaft for said grindstones extending coaxially through a hollow in said cylindrical member, a thrust bearing for said drive shaft mounted on said slide, and drive means for said main drive shaft, horizontal arms pivotally mounted on said main drive shaft, grindstones mounted on said arms, and drive transmissions connecting said main drive shaft with said grindstones.

7:. In a cloth-cutting machine of the reciproeating knife type having vertical slide for moving grindstones along the knife for sharpening purposes, a support having guideways for said slide, a vertical cylindrical member rotatively mounted on said support and having an endless peripheral thread with a section extending down and continuing into a section extending up and connecting with the top of said downwardly extending section, means for rotating said cylindrical member, a follower mounted on said slide and engaging said endless peripheral thread for reciprocating said vertical slide, a main drive shaft for said grindstones extending coaxially through a hollow in said cylindrical member, a thrust bearmg for said drive'shaft mounted on said slide,

and drive means for said main drive shaft, hori- UNITED STATES PATENTS zontal arms pivotally mounted on said main drive shaft, grindstones mounted on said arms, and Number Name Date drive transmissions connecting said main drive 2,171,603 Segal Sept. 5, 1939 shaft with said grindstones, and mounted on and 5 2,156,798 Bangser May 2, 1939 extending along said horizontal arms. 1,941,501 Steiner Jan 2, 1934 MOEv STEINER- 2,060,197 Greenbaum Nov, 10, 1936 REFERENCES CITED The following references are of record in the 10 file of this patent: 

